You can put this solution on YOUR website! Solve the system by elimination.
-4x-5y-z=18
-2x-5y-2z=12
-2x+5y+2z=4
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Pick a variable to eliminate 1st.
All y terms have the same coefficient 5:
---
-4x-5y-z=18
-2x-5y-2z=12
------------------ Subtract
-2x + z = 6 Eqn A
---
-2x-5y-2z=12
-2x+5y+2z=4
--------------------- Add
-4x = 16
--> x = -4 ************
---
-2x + z = 6 Eqn A
--> z = -2 ************
---
-2x+5y+2z=4
--> y = 0 *************
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(-4,0,-2)
